Ullage rod



May 12, 1936. w. H. MARSDEN -ULLAGE 'ROD Filed June 26, 1935' 'alongsideand marked the contents can be accurately measured. The

Patented May 12, 1936 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to a tank content measuring instrument, morespecifically an ullage rod for measuring the contents of gasoline tanksin filling stations.

The large oil companies make a practice of calibrating at eachfillingstation several times each year because of the danger of a tanksettling or being thrown out of position in any other way. The practiceis to use an ullage rod in checking the contents by graduations, andonce the rod has been accurately calibrated, an ordinary wooden rod ofthe same displacement, suitable for everyday use by the stationattendants, is laid to agree with it, so that ullage rods heretoforeavailable were subject to various practical objections which it is theobject of the present invention to avoid, as hereinafter described.

The invention is illustrated in the accompanying drawing, in which-Figure 1 is a front view of an ullage rod made in accordance with myinvention, showing a middle portion broken away to permit showing therod on a larger scale within the confines of the sheet, and showing anupper portion in section for purposes of better illustration;

Figs. 2 and 3 are sections on the correspondingly numbered lines ofFigure 1, and

Fig. 4 is a longitudinal section on the broken line 44 of Fig. 2.

The same reference numerals are applied to corresponding partsthroughout the views.

- The rod has the body or casing I thereof formed by a piece of roundtubing of suitable length, and into the lower end of this tube a metalplug H has its reduced portion I2 entered with a press fit to serve as aclosure and bottom for the tube. Another plug I3 has a reduced portionI4 entered with a press fit in the upper end of the tube. While a roundtube is shown, it should, of course, be understood that I may employ oneof square or rectangular cross-section, or any other shape suitable forthe present purpose. A longitudinal slot I5 is provided in the wall ofthe tubular body I0 to serve as a sight opening, and directly behind andvisible through the slot is a glass gauge tube l6 suitably cemented atits upper and lower ends in holes I! and I8 in the top and. bottomplugs, respectively. An atmospheric vent IS in the top plug communicateswith the upper end of the tube I 6. Passages and 2| are drilled in thebottom plug II to establish communication between the lower end of thetube l6 and a parallel bore 22 in the plug H. The latter opens at itslower end into a chamber 23 in the bottom of the plug l I, opening fromthe bottom of the plug and through a hole 24 to the side of the the bore22 at 25 aifords a guide for a longitudinal rod 26 which extends throughthe bore 22 and constitutes the stem for a valve 21 adapted to engage aseat 28 adjacent the lower end of the bore 22 to seal the bore and trapliquid in the tube I6. The valve 21 is suitably threaded on a reducedlower end portion of the rod 26 as shown, and has a lock nut 29 threadedbeneath and jammed against it. A coiled compression spring 30 fitsaround the rod 26 in the bore 22 and acts between the upper end of thebore and the valve 27 to normally urge the valve downwardly away fromthe seat 28. The rod 26 extends through a bushing 3| in the top plug l3and has a fiat end 32 pivoted as at 33 in the forked lower end of a handlever 35. The end of the forked portion 34 is provided with a camsurface 36 for engagement with the fiat top surface of the bushing 3|,whereby to permit the rod 26 to be drawn upwardly against the action ofthe spring 30 by moving the handle 35 in a counterclockwise direction asviewed in Figs. 1 and 4 from the horizontal position indicated in dottedlines to the substantially vertical full line position. The eccentricityof the cam surface 36 is graduated so as to permit one to draw up thevalve firmly to its seat and thus definitely eliminate danger ofleakage. The length of the rod 26 insures sufiicient stretch in thismember so that the valve will be seated resiliently but so firmly thatleakage is avoided even though there is metal to metal contact betweenthe valve and seat. In the event the wear caused in the operation of thecam surface 36 on the top of the bushing 3| gives rise to the valve 21being seated too lightly for an oiltight seal, the operator can remedythe difliculty by merely unscrewing the bushing 3| a trifle to take upfor wear, after which the valve can be seated just as tightly as whenthe parts were new. Leakage along the rod 26 is prevented by packingmaterial at 31 above the guide 25, compressed by a gland nut 38.

In calibrating, considerable time is lost in waiting for the turbulenceto subside in the tank after gasoline has been added. I propose to addgasoline by pouring it in through the filler hole 39 in the top plug l3,using a funnel entered in the hole, and allowing the gasoline to spillwith minimum violence from the lower end of the rod through verticalslots 40 provided preferably in equally circumferentially spacedrelation on the lower plug. A reduction in end of the rod, reaching ashort distance up from the bottom plug l I, as shown. In this way thereis no appreciable agitation of the gasoline in the tank and one may takea reading shortly after adding the gasoline with reasonable assurance ofaccuracy.

In operation, it is the practice to enter the rod in the tank with thevalve 21 in open position, as indicated by the dotted horizontalposition of the lever 35 in Fig. 4. The gasoline in the tank is,therefore, free to rise in the gauge tube [6 to the same level asprevails in the tank. Then, assuming that the rod is in a true verticalposition for accurate measurement of the depth of gasoline in the tank,the operator closes the valve 21 by moving the handle 35 to verticalposition, drawing up tightly on the valve in doing so, to insure againstleakage of any gasoline from the tube l6. After removal of the rod, atleast.

far enough to permit marking in accordance with the level in the tube,the rod is then returned to its position resting on the bottom of thetank, and the valve 21 is opened so that the operation described can berepeated after a measured amount of gasoline has been added to thecontents of the tank. As previously explained, the addition of measuredamounts of gasoline through the rod itself, so as to spill out from thelower end, minimizes agitation of the tanks contents and in that way thework of calibrating is speeded up considerably.

While I have described the invention with particular reference to itsuse in connection with gasoline tanks, it should be understood that myinvention is not limited to this specific application but is useful inconnection with any tank filled and emptied in a similar way, regardlessof the kind of liquid stored. The appended claims have accordingly beendrawn so as to cover all legitimate modifications and adaptations.

I claim:

1. A device of the class described comprising an elongated tubular rodhaving an open ended transparent gauge tube mounted lengthwise thereinand visible from the side thereof, said rod having a liquid inlet in thelower end thereof communicating with the lower end of said tube, a valvemovable upwardly toward a seat in the low- 7 er end of said rod to closethe liquid inlet, a stem extending upwardly from the valve lengthwisethrough the rod and projecting from the upper end thereof, said valvetending normally to move downwardly away from its seat, and a flat endedhand lever pivoted on a horizontal axis on the upper end of said stemand movable from a transverse position relative to the stem to avertical dead-center position in alignment with the stem and restingwith its flat end on top of said rod to raise the valve and force thesame tightly against its seat, said lever having one side of the flatend rounded to provide a cam surface for sliding engagement on the upperend of said rod whereby to force the valve against its seat by camaction, the opposite side of said flat end being square, whereby toprevent movement of said lever past dead-center position.

2. An ullage rod as set forth in claim 1 including a verticallyadjustable threaded bearing member for engagement by the lower end ofsaid handle, whereby to adjust the valve and stem relative to the valveseat.

WILLIAM H. MARSDEN.

